These resources have been reviewed and selected by STEM Learning’s team of education specialists for factual accuracy and relevance to teaching STEM subjects in UK schools.

Substances Changing: Reaction on Heating

These downloadable videos and animations are part of the multimedia package Stuff and Substance, developed by the Gatsby Science Enhancement Programme (SEP). They can be used to develop the idea of chemical change by showing a reaction that takes place on heating to a higher temperature.

These resources cover the reaction between magnesium and oxygen. When heating magnesium in the open air the consumption of oxygen is not directly observable. Many students find the traditional experiment of monitoring mass changes difficult to interpret, especially if they think ‘gases’ such as oxygen have no mass. The approach here is novel, in that pure oxygen is held within a plastic bag attached to a test-tube containing magnesium. One video shows the bag collapsing as the magnesium reacts. The animations represent the changes of substances in terms of atoms and give practice at constructing a word equation. Other videos contrast heating magnesium and copper in the open air.

These video and animation files form part of the resources in the section Substances Changing in the Stuff and Substance multimedia package, which provides a series of interactive pages that can be used by teachers or students in the classroom.

Please note: From 2021, Adobe has discontinued support for Flash player and as a result some interactive files may no longer be playable. As an alternative method to accessing these files a group of volunteers passionate about the preservation of internet history have created project Ruffle ( Ruffle is an entirely open source project that you can download and run many interactive Flash resources. For further information regarding STEM Learning’s policy for website content, please visit our terms and conditions page.

Show health and safety information

Please be aware that resources have been published on the website in the form that they were originally supplied. This means that procedures reflect general practice and standards applicable at the time resources were produced and cannot be assumed to be acceptable today. Website users are fully responsible for ensuring that any activity, including practical work, which they carry out is in accordance with current regulations related to health and safety and that an appropriate risk assessment has been carried out.

Information on the permitted use of this resource is covered by the Category Three Content section in STEM Learning’s Terms and conditions.